1. Field of the Invention
The present invention relates to a cleaning method and a cleaning apparatus used for performing the cleaning method.
2. Description of Related Art
Generally, to remove contamination or foreign matter from a member (a machined part or component, for example) which has adhered to the member during a manufacturing process of the member, or to remove remaining chemical liquid from the member which has been applied to the surface of the member during a surface treatment process of the member, a cleaning apparatus is used for injecting water or cleaning fluid to the member. Japanese Patent Application Laid-open No. 2005-296874 describes such a cleaning apparatus of the two-fluid nozzle type, which has a fluid injection nozzle for injecting fluid and a gas injection nozzle for injecting gas radially outward for reducing the mean particle diameter of droplets of the fluid injected from the fluid injection nozzle.
However, the cleaning apparatus of the two-fluid nozzle type as described in the above patent document has a problem in that it consumes a large amount of gas because the gas-liquid volume ratio representing the volume ratio of the gas injected from the gas injection nozzle to the fluid injected from the fluid injection nozzle has to be kept between 800 and 1000 in order to make the droplets sufficiently small.